基于ICA的在线掌纹识别

个人身份认证和鉴别在现在社会显示着重要的作用,作为一种准确而可靠的个人鉴定方式,生物识别已经引起了广泛的注意.掌纹作为一种相对较新的生物识别技术也有着独特的优点.而掌纹特征的提取和选择是整个识别中最关键的一个环节,主要利用ICA（独立主成分分析）方法对掌纹进行特征提取,实验证明,相比较PCA（主成分分析）方法,基于ICA方法具有更高的识别效率.     

山地高原地区TM影像水体信息提取方法比较-以香格里拉县部分地区为例

采用遥感数据对地物进行识别是获取地物信息的一种重要手段。在云南省香格里拉县湿地研究中,以Land-sat ETM+影像作数据源,分别采用了阈值法、差值法和阈值法的结合运用、多波段谱间关系法和阈值法的结合运用3种方法对湿地进行识别。结果表明:采用阈值法难以将灰度值接近的山体阴影和水体区分开来,差值法和阈值法的结合、多波段谱间关系法和阈值法的结合运用提取到的水体信息精度较高,多波段谱间关系法对于消除阴影的效果最好。     

Perceptual encryption with compression for secure vector map data processing

With the rapidly rising interest in geographic information system (GIS) contents, a large volume of valuable map data has been unlawfully distributed by pirates. Therefore, the secure storage and transmission of classified national digital map datasets have been increasingly threatened. As the importance of secure, large-volume map datasets has increased, vector map security techniques that focus on secure network and data encryption have been studied. These techniques are required to ensure access control and prevent illegal copying of digital maps. This paper presents perceptual encryption on the vector compression domain for copy protection and access control of vector maps. Our algorithm compresses all vector data of polylines and polygons by lossless minimum coding object (MCO) units and perceptually encrypts using two processes using the mean points and directions of MCOs. The first process changes the position of vector data by randomly permuting the mean points of MCOs, the so-called position encryption. The second process changes the geographic shape by circularly encrypting the directions of vertices in MCOs by the XOR operator. Experimental results have verified that our algorithm can encrypt GIS digital maps effectively and simply and can also improve the compression ratio, unlike general data encryption techniques, and thus, our algorithm is very effective for a large volume of GIS datasets.     

Enhancing clustering quality of geo-demographic analysis using context fuzzy clustering type-2 and particle swarm optimization

Geo-Demographic Analysis, which is one of the most interesting inter-disciplinary research topics between Geographic Information Systems and Data Mining, plays a very important role in policies decision, population migration and services distribution. Among some soft computing methods used for this problem, clustering is the most popular one because it has many advantages in comparison with the rests such as the fast processing time, the quality of results and the used memory space. Nonetheless, the state-of-the-art clustering algorithm namely FGWC has low clustering quality since it was constructed on the basis of traditional fuzzy sets. In this paper, we will present a novel interval type-2 fuzzy clustering algorithm deployed in an extension of the traditional fuzzy sets namely Interval Type-2 Fuzzy Sets to enhance the clustering quality of FGWC. Some additional techniques such as the interval context variable, Particle Swarm Optimization and the parallel computing are attached to speed up the algorithm. The experimental evaluation through various case studies shows that the proposed method obtains better clustering quality than some best-known ones.     

Conjugate natural convection heat transfer in a partitioned differentially-heated square cavity

In this study numerical results for conjugate natural convection flow and heat transfer in a differentially-heated square cavity divided by a partition with finite thickness and thermal conductivity are presented. A series of numerical simulation is carried out using the finite volume method over a wide range of the Rayleigh number (10⁵–10⁹), with three dimensionless partition thicknesses (0.05, 0.1 and 0.2) and three dimensionless partition positions (0.25, 0.5 and 0.75), both are non-dimensionalized by the cavity width. The results show that the average Nusselt number increases with the Rayleigh number but decreases with partition thickness. It is also found that the partition position has a negligible effect on the average Nusselt number for the whole range of Rayleigh number considered.     

An Intelligent,multi-transducer signal conditioning design for manufacturing applications

This paper describes a flexible, intelligent, high bandwidth, signal conditioning reference design and implementation, which is suitable for a wide range of force and displacement transducers in manufacturing applications. The flexibility inherent in the design has allowed more than 10 specialised transducer conditioning boards to be replaced by this single design, in a range of bespoke mechanical test equipment manufactured by the authors. The board is able to automatically reconfigure itself for a wide range of transducers and calibrate and balance the transducer. The range of transducers includes LVDT, AC/DC strain gauge and inductive bridges, and a range of standard industrial voltage current interface transducers. Further, with a minor low-cost addition to the transducer connector, the board is able to recognise the type of transducer, reconfigure itself and store the calibration data within the transducer, thereafter allowing a plug-and-play operation as transducers are changed. The paper provides an example of the operation in typical manufacturing test application and illustrates the stability and noise performance of the design.     

Feasibility of tracking laparoscopic instruments in a box trainer using a Leap Motion Controller

Motion analysis is employed to assess minimally invasive surgical psychomotor skills in box trainers. Tracking of laparoscopic instruments requires sensor-based systems that can be expensive, limit movements and modify their ergonomic properties. We evaluate the feasibility of using Leap Motion as a cheap, unobtrusive alternative. Four experiments were performed to determine its precision while tracking a laparoscopic instrument inside and outside a box trainer. Static long and short term precision of the Leap Motion was <2.5 mm. Precision between 12 different positions within the box trainer was <0.7 mm for all measured distances between neighbors. Dynamic precision when moving the instrument for 200 mm ranged between 2 and 15 mm. Leap Motion presents acceptable precision values inside a box trainer. Improvements are still required (e.g.: multiple instruments’ tracking). Once solved, a validation study should verify the usefulness of Leap Motion to objectively measure skills of novices and residents during training.     

Quantum theory analysis on microscopic mechanism of the interaction of laser with cell membrane

On the basis of liquid crystal model with the electric dipole moment of cell membrane,the microscopic mechanism of the electricity and thermology effects of interaction of laser with cell membrane is researched by electromagnetic, quantum mechanics and quantum statistics. We derive the formulas on the polarization effects and ＂temperature-rising effect＂ of laser-cell membrane interaction. The results of the theoretical research can explain some experiments.     

价格波动时商品动态价格的数学模型、物价稳定性与宏观调控分析

本文研究有价格波动时,商品动态价格的数学模型、物价稳定性与宏观调控问题。首先,在价格有波动时,建立了商品动态价格(与时间和销售量都有关)的数学模型,并给出动态价格最优的条件;其次,通过理论上比较动态价格和政府指导价(称为“稳定价格”)的销售利润,得到保持物价稳定和进行宏观调控的理论依据;最后,提出了商品的预期利润与销售量之间关系的一个二维微分方程模型,并通过分析模型给出需求最大价格和利润增长价格的下限估计。     

基于VBA的成绩分析

介绍了考试成绩分析中用VBA对Excel进行二次开发涉及的关键技术,包括VBA代码与Excel原有界面元素的交互、成绩统计量的动态计算、工作表的复制与删除、用多种格式显示数据、数据的安全性等。在考试成绩分析中将重复操作用VBA编程实现,能使部分工作自动化,从而提高了工作效率和计算的正确性,减轻了教师的工作量。